We study Bernstein-type and Nikol’skii-type estimates for an arbitrary algebraic polynomial in regions of the complex plane.
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F. G. Abdullayev and V. V. Andrievskii, “On the orthogonal polynomials in the domains withK-quasiconformal boundary,” Izv. Akad. Nauk Azerb. SSR, Ser. Fiz., Tech., Mat., No. 1, 3–7 (1983).
F. G. Abdullaev, “On some properties of orthogonal polynomials over an area in domains of the complex plane. I,” Ukr. Mat. Zh., 52, No. 12, 1587–1595 (2000); Ukr. Math. J., 52, No. 12, 1807–1817 (2000).
F. G. Abdullaev, “On some properties of orthogonal polynomials over an area in domains of the complex plane. II,” Ukr. Mat. Zh., 53, No. 1, 3–13 (2001); Ukr. Math. J., 53, No. 1, 1–14 (2001).
F. G. Abdullaev, “On some properties of orthogonal polynomials over an area in domains of the complex plane. III,” Ukr. Mat. Zh., 53, No. 12, 1588–1599 (2001); Ukr. Math. J., 53, No. 12, 1934–1948 (2001).
F. G. Abdullayev, “On the interference of the weight and boundary contour for orthogonal polynomials over the region,” J. Comput. Anal. Appl., 6, No. 1, 31–42 (2004).
F. G. Abdullayev, “The properties of the orthogonal polynomials with weight having singularity on the boundary contour,” J. Comput. Anal. Appl., 6, No. 1, 43–59 (2004).
F. G. Abdullayev and U. Deger, “On the orthogonal polynomials with weight having singularity on the boundary of regions of the complex plane,” Bull. Belg. Math. Soc., 16, No. 2, 235–250 (2009).
F. G. Abdullayev and D. Aral, “The relation between different norms of algebraic polynomials in the regions of complex plane,” Azerb. J. Math., 1, No. 2, 70–82 (2011).
F. G. Abdullayev and C. D. Gün, “On the behavior of the algebraic polynomials in regions with piecewise smooth boundary without cusps,” Ann. Polon. Math., 111, 39–58 (2014).
F. G. Abdullayev and N. P. Ozkartepe, “Uniform and pointwise Bernstein–Walsh-type inequalities on a quasidisk in the complex plane,” Bull. Belg. Math. Soc., 23, No. 2, 285–310 (2016).
F. G. Abdullayev and T. Tunc, “Uniform and pointwise polynomial inequalities in regions with asymptotically conformal curve on weighted Bergman space,” Lobachevskii J. Math., 38, No. 2, 193–205 (2017).
F. G. Abdullayev, T. Tun¸c, and G. A. Abdullayev, “Polynomial inequalities in quasidisks on weighted Bergman spaces,” Ukr. Mat. Zh., 69, No. 5, 582–598 (2017); Ukr. Math. J., 69, No. 5, 675–695 (2017).
K. Astala, “Analytic aspects of quasiconformality,” Doc. Math. J., Extra vol. ICM II, 617–626 (1998).
L. V. Ahlfors, Lectures on Quasiconformal Mappings, D. Van Nostrand, Toronto (1966).
J. M. Anderson, F. W. Gehring, and A. Hinkkanen, Polynomial Approximation in Quasidisks, Springer, Berlin (1985).
V. V. Andrievskii, “Constructive characterization of harmonic functions in domains with quasiconformal boundary,” in: Quasiconformal Continuation and Approximation by Function in a Set of the Complex Plane [in Russian], Kiev (1985).
V. V. Andrievskii, V. I. Belyi, and V. K. Dzyadyk, Conformal Invariants in Constructive Theory of Functions of Complex Variable, World Federation Publ. Co., Atlanta (1995).
V. V. Andrievskii, “Weighted polynomial inequalities in the complex plane,” J. Approxim. Theory, 164, No. 9, 1165–1183 (2012).
S. Balci, M. Imash-kyzy, and F. G. Abdullayev, “Polynomial inequalities in regions with interior zero angles in the Bergman space,” Ukr. Mat. Zh., 70, No. 3, 318–336 (2018); Ukr. Math. J., 70, No. 3, 362–384 (2018).
I. M. Batchaev, Integral Representations in the Regions With Quasiconformal Boundary and Some of Their Applications [in Russian], Author’s Abstract of the Candidate-Degree Thesis (Physics and Mathematics), Baku (1981).
D. Benko, P. Dragnev, and V. Totik, “Convexity of harmonic densities,” Rev. Mat. Iberoam., 28, No. 4, 1–14 (2012).
S. N. Bernstein, “Sur la limitation des dérivées des polynomes,” C. R. Math. Acad. Sci. Paris, 190, 338–341 (1930).
S. N. Bernstein, “On the best approximation of continuous functions by polynomials of a given degree,” Izd. Akad. Nauk SSSR, 1 (1952); 2 (1954).
P. P. Belinskii, General Properties of Quasiconformal Mappings [in Russian], Nauka, Novosibirsk (1974).
Z. Ditzian and S. Tikhonov, “Ul’yanov and Nikol’skii-type inequalities,” J. Approxim. Theory, 133, No. 1, 100–133 (2005).
Z. Ditzian and A. Prymak, “Nikol’skii inequalities for Lorentz spaces,” Rocky Mountain J. Math., 40, No. 1, 209–223 (2010).
V. K. Dzyadyk, Introduction to the Theory of Uniform Approximation of Function by Polynomials [in Russian], Nauka, Moscow (1977).
V. Kabayla, “On some interpolation problems in the class Hp for p < 1,” Dokl. Akad. Nauk SSSR, 132, No. 5, 1002–1004 (1960).
O. Lehto and K. I. Virtanen, Quasiconformal Mapping in the Plane, Springer, Berlin (1973).
F. D. Lesley, “Hölder continuity of conformal mappings at the boundary via the strip method,” Indiana Univ. Math. J., 31, 341–354 (1982).
D. I. Mamedhanov, “Inequalities of S. M. Nikol’skii type for polynomials in the complex variable on curves,” Sov. Math. Dokl., 15, 34–37 (1974).
G. V. Milovanovic, D. S. Mitrinovic, and Th. M. Rassias, Topics in Polynomials: Extremal Problems, Inequalities, Zeros, World Scientific, Singapore (1994).
P. Nevai and V. Totik, “Sharp Nikolskii inequalities with exponential weights,” Anal. Math., 13, No. 4, 261–267 (1987).
S. M. Nikol’skii, Approximation of Functions of Several Variables and Embedding Theorems, Springer, New York (1975).
Ch. Pommerenke, Univalent Functions, Vandenhoeck & Ruprecht, Göttingen (1975).
Ch. Pommerenke, Boundary Behaviour of Conformal Maps, Springer, Berlin (1992).
I. Pritsker, “Comparing norms of polynomials in one and several variables,” J. Math. Anal. Appl., 216, 685–695 (1997).
G. Szegö and A. Zygmund, “On certain mean values of polynomials,” J. Anal. Math., 3, No. 1, 225–244 (1953).
S. E. Warschawski, “On differentiability at the boundary in conformal mapping,” Proc. Amer. Math. Soc., 12, 614–620 (1961).
S. E. Warschawski, “On Hölder continuity at the boundary in conformal maps,” J. Math. Mech., 18, 423–427 (1968).
J. L. Walsh, Interpolation and Approximation by Rational Functions in the Complex Domain, American Mathematical Society, Providence, RI (1960).
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Translated from Ukrains’kyi Matematychnyi Zhurnal,Vol. 73, No. 4, pp. 439–454, April, 2021. Ukrainian DOI: 10.37863/umzh.v73i4.6306.
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Abdullayev, F.G., Gün, C.D. Bernstein–Nikol’skii-Type Inequalities for Algebraic Polynomials from the Bergman Space in Domains of the Complex Plane. Ukr Math J 73, 513–531 (2021). https://doi.org/10.1007/s11253-021-01940-z
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DOI: https://doi.org/10.1007/s11253-021-01940-z